Around 600 English Defence League (EDL) marchers descended on the town of Dudley on Saturday.

Police said around 50 people turned out to oppose the protest but were prevented from reaching the main march by police.

The local council said many local businesses were forced to stay closed during Saturday shopping hours because of anxiety about the potential of violence.

“While West Midlands Police has no power to ban people from exercising their democratic right to express their opinions through protest, we have been planning the policing operation for months,” Chief Superintendent Chris Johnson, who is responsible for policing in the town, said.

Peter Lowe, the Labour leader of Dudley Council, said the local authority was powerless to stop the march.

“The fear and anxiety caused by these kinds of protests meant that the majority of businesses did not open on what would normally be their busiest day’s trade,” he said.

“We have said all along that the EDL is not welcome in Dudley borough but there are no legal powers to stop them holding a protest.”

West Midlands Police said today that 25 of the 30 people arrested were detained “to prevent an imminent breach of the peace and were later released without charge”.

Ahead of the march one EDL supporter threatened on Facebook to burn the mosque down, the website EDL Newsreports. The social media post in which the threat was allegedly made has since been removed.

Ahead of the protest, the English Defence League (Manchester division) Facebook group posted a statement to its supporters: “I’m sure everyone remembers the last [march] held here in 2010 where we were forced to hold the event in a car park on the edge of town. Well not this time!”

The Unite Against Fascism group, which called on its supporters to oppose the EDL protest, tweeted images of the counter-demonstration and said it was “standing in solidarity against the racist EDL”.